Signaling Recognition Events with Fluorescent Sensors and Switches.

Great attention is currently paid to the synthesis of polynuclear transition metal complexes and the study of their photochemical, photophysical, and electrochemical properties. This interest is stimulated, in particular, by attempts to design and construct multicomponent systems (often called supramolecular species) capable of performing useful lightand/or redox-induced functions.1-16 A great deal of investigations on mononuclear transition metal complexes had previously shown that several families of these compounds are very interesting from the electrochemical, photochemical, and photophysical viewpoints.17-22 The metalligand interaction, in fact, is often (i) weak enough to allow the manifestation of intrinsic properties of metal and ligands (e.g., ligand-centered and metalcentered absorption bands and redox waves) and, at the same time, (ii) strong enough to cause the appearance of new properties, characteristic of the whole compound (e.g., metal-to-ligand or ligand-tometal charge-transfer bands). On passing from mononuclear to polynuclear transition metal complexes, the situation becomes even more interesting because in the latter (supramolecular) compounds one can find, besides properties related to each metal-based component, properties related to the structure and composition of the whole array. A suitable choice of the mononuclear building blocks and bridging ligands and an appropriate design of the (supramolecular) structure can in fact allow the occurrence of very interesting and potentially useful processes such as energy transfer along predetermined pathways, photoinduced charge separation, multielectron exchange at a predetermined potential, etc. The knowledge on the luminescence and redox properties of polynuclear transition metal complexes is rapidly accumulating, but it is disperse in a great number of journals. We have made an attempt to collect the available results, and we present them together with some fundamental introductory concepts and a few comments. One of the main problems, of course, was to delimit the field of this review. Using personal criteria which are related to our own research interests, we decided to consider only polynuclear transition metal complexes that can be defined as supramolecular species (section 2.2) and that are reported to exhibit luminescence. For such compounds only, the electrochemical properties have also been reviewed. Furthermore, we decided to include only classical (Werner-type) polynuclear transition metal compounds where the number of metal-based units is exactly known and the connection between the metal centers is provided only by bridging ligands. Thus, a number of interesting systems such as polymer-appended metal † In memoriam of Mauro Ciano. 759 Chem. Rev. 1996, 96, 759−833

Luminescent and Redox-Active Polynuclear Transition Metal Complexes.

http://nathan.instras.com/documentDB/paper-12.pdf

Applications of functionalized transition metal complexes in photonic and optoelectronic devices

New Self-Assembled Structural Motifs in Coordination Chemistry.

Artificial photosynthesis: molecular systems for catalytic water oxidation.

Ruthenium(II) and Osmium(II) Bis(terpyridine) Complexes in Covalently-Linked Multicomponent Systems: Synthesis, Electrochemical Behavior, Absorption Spectra, and Photochemical and Photophysical Properties

Photoinduced processes in dyads and triads containing a ruthenium(II)-bis(terpyridine) photosensitizer covalently linked to electron donor and acceptor groups

We have synthesized the luminescent Os(ttp) 2 2+ photosensitizer (P) and the supramolecular species P-A, D-P, and D-P-A where the photosensitizer is covalently linked to the electron acceptor MV 2+ (A) and /or the electron donors PTZ or DPAA (D); ttp is 4'-(p-tolyl)-2,2':6',2''-terpyridine, MV 2+ is methylviologen, PTZ is phenothiazine, and DPAA is di-p-ansylamine

Photoinduced process in dyads and triads: an osmium(II)-bis(terpyridine) photosensitizer covalently linked to electron donor and acceptor groups

2,2′ : 6′,2″-Terpyridine ligands have been modified so as to bear an electron acceptor or an electron donor group; efficient intramolecular vectorial electron transfer has been shown to occur in an osmium complex from its metal-to-ligand charge transfer excited state.

Ruthenium and osmium complexes of 2,2′ : 6′,2″-terpyridine covalently linked to electron acceptor and electron donor groups

Photoinduced charge separation in dyads and triads containing a ruthenium(II)- or osmium(II)-bis-terpyridine photosensitizer covalently linked to electron donor and acceptor groups

Stephane Guillerez

Papers

Ruthenium(II) and Osmium(II) Bis(terpyridine) Complexes in Covalently-Linked Multicomponent Systems: Synthesis, Electrochemical Behavior, Absorption Spectra, and Photochemical and Photophysical Properties

Photoinduced processes in dyads and triads containing a ruthenium(II)-bis(terpyridine) photosensitizer covalently linked to electron donor and acceptor groups

Photoinduced process in dyads and triads: an osmium(II)-bis(terpyridine) photosensitizer covalently linked to electron donor and acceptor groups

Ruthenium and osmium complexes of 2,2′ : 6′,2″-terpyridine covalently linked to electron acceptor and electron donor groups

Photoinduced charge separation in dyads and triads containing a ruthenium(II)- or osmium(II)-bis-terpyridine photosensitizer covalently linked to electron donor and acceptor groups